field depending

good afternoon, how can I change the value of the field depending on the entered value of others. field1 -entered, field2 - entered, field3=filed1+field2?

hello
you mean an addition or an concat value ?
concat for now its only possible via 2 things :
- concat field for form (field3 value will be calculate after save):
create field3 (a text field)
add empty value in defaut value like a space
set remove space option
set this defaut value for all new item
in prefix add {{namefield1}} {{namefield2}}
you can put your field3 in position

- concat or operation
your field 1 - 2 in render position of template
use php to display you fields and do php operation

with pro plugin you can do operation in text field but not accessible for now